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91.

Background/Aim:

Clostridium difficile infection (CDI) can affect up to 8% of hospitalized patients. Twenty-five percent CDI patients may develop C. difficile associated diarrhea (CDAD) and 1–3% may progress to fulminant C. difficile colitis (FCDC). Once developed, FCDC has higher rates of complications and mortality.

Patients and Methods:

A 10-year retrospective review of FCDC patients who underwent colectomy was performed and compared with randomly selected age- and sex-matched non-fulminant CDAD patients at our institution. FCDC (n=18) and CDAD (n=49) groups were defined clinically, radiologically, and pathologically. Univariate analysis was performed using Chi-square and Student''s t test followed by multivariate logistic regression to compute independent predictors.

Results:

FCDC patients were significantly older (77 ± 13 years), presented with triad of abdominal pain (89%), diarrhea (72%), and distention (39%); 28% had prior CDI and had greater hemodynamic instability. In contrast, CDAD patients were comparatively younger (65 ± 20 years), presented with only 1 or 2 of these 3 symptoms and only 5% had prior CDI. No significant difference was noted between the 2 groups in terms of comorbid conditions, use of antibiotics, or proton pump inhibitor. Leukocytosis was significantly higher in FCDC patients (18.6 ± 15.8/mm3 vs 10.7 ± 5.2/mm3; P=0.04) and further increased until the point of surgery. Use of antiperistaltic medications was higher in FCDC than CDAD group (56% vs 22%; P=0.01).

Conclusions:

Our data suggest several clinical and laboratory features in CDI patients, which may be indicative of FCDC. These include old age (>70 years), prior CDI, clinical triad of increasing abdominal pain, distention and diarrhea, profound leukocytosis (>18,000/mm3), hemodynamic instability, and use of antiperistaltic medications.  相似文献   
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Optimal visualization is one of the most challenging aspects of performing vitreoretinal surgery. In situations where conventional microscopic techniques provide poor posterior visualization, the adjunctive skill set of endoscopic visualization may be needed. This allows for by-passing the opaque anterior segment media and getting access to the posterior segment pathology. Endoscopic vitrectomy is a useful and unique adjunct to microincision vitreoretinal surgery. The optical set-up of endoscopy allows for clinical approaches that are impossible with regular microscope viewing systems. These include the ability to observe across optically significant anterior segment opacities and directly visualize the posterior segment of the eye. It also allows for visualizing the difficult-to-access retroirideal, retrolental, and anterior retinal structures. Surgical access to anatomic spaces like the pars plana, pars plicata, ciliary sulcus, ciliary body, and peripheral lens is tedious. This is made simpler by endoscopy. In this review, we summarize and review the usage of the intraocular endoscope as a diagnostic and therapeutic armamentarium across a wide spectrum of ocular pathologies.  相似文献   
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Purpose:Deeply embedded corneal foreign bodies and intrastromal foreign body removal can often be a challenge. The aim of this report was to describe the utility of endoscopy in visualization and removal of an embedded corneal bee stinger.Methods:A 44-year-old male patient developed toxic keratopathy after injury from a bee stinger. On examination, the bee stinger was noted to be deeply embedded in the corneal stroma. A superficial keratectomy was initially attempted; however, the stinger was noted to be intrastromal and protruding into the anterior chamber and could not be removed. An Endoscopy-assisted visualization was used to remove the stinger.Results:The bee stinger was successfully removed and the patient''s vision improved to 20/100 from an initial CFCF (counting fingers close to face) at time of presentation. At the end of 3 months follow-up, there was residual corneal edema along with cataractous changes in the lens as a sequelae of the initial bee sting injury. The patient subsequently underwent an endothelial keratoplasty along with phacoemulsification with intraocular lens implantation and the final BCVA improved to 20/40.Conclusion:Endoscopyassisted visualisation of anterior chamber and angle structures can be valuable in removal of retained and deeply embedded corneal or intracameral foreign bodies.  相似文献   
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The focusing response of the human eye — accommodation — exhibits errors known as lags and leads. Lags occur when the stimulus is near and the eye appears to focus farther than the stimulus. Leads occur with far stimuli where the eye appears to focus nearer than the stimulus. We used objective and subjective measures simultaneously to determine where the eye is best focused. The objective measures were made with a wavefront sensor and an autorefractor, both of which analyze light reflected from the retina. These measures exhibited typical accommodative errors, mostly lags. The subjective measure was visual acuity, which of course depends not only on the eye''s optics but also on photoreception and neural processing of the retinal image. The subjective measure revealed much smaller errors. Acuity was maximized at or very close to the distance of the accommodative stimulus. Thus, accommodation is accurate in terms of maximizing visual performance.  相似文献   
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